From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-4.1 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 5D08BC433E1 for ; Wed, 29 Jul 2020 02:28:23 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 3B2A32070B for ; Wed, 29 Jul 2020 02:28:23 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="F2LZlYX7" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731152AbgG2C2W (ORCPT ); Tue, 28 Jul 2020 22:28:22 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:33888 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1731062AbgG2C2V (ORCPT ); Tue, 28 Jul 2020 22:28:21 -0400 Received: from mail-pl1-x643.google.com (mail-pl1-x643.google.com [IPv6:2607:f8b0:4864:20::643]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 59EFCC061794; Tue, 28 Jul 2020 19:28:21 -0700 (PDT) Received: by mail-pl1-x643.google.com with SMTP id t10so5769076plz.10; Tue, 28 Jul 2020 19:28:21 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to; bh=w5wshDDSYg1LYpcAUeQIV+9c4+ZcOe7Ex7p3INomeN4=; b=F2LZlYX76zy/c5Rrzvh6td9p/UFAQUEFskEcInNrz4Pf/kKNmvsvRXxT0eoYjQQFev GsWqN0kUqnPlvQJFX4XkoXo4FBeAXrzpw6iHCf//YuaaYCTEHXsjqgklSnAItMSvqgGK 5hxnp24WScuCn154vv7d5xdc0BwyBCsVw2HE1irv/GqZZPSBA5gmV5+OApoNYSEdpqg+ 9I4DKy22Dkek4JHojU3qZMnYFLhtH8N3dRWu2mw+i3CkxBrIARktiNOJKqfrM+N3ErIG pUPx88kpFf5f0KSZCyAjcKFfpK1bWwFJooeRQ2k+G6PfYMPJZql1rY7cINH2KiHHR4aQ GHpQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to; bh=w5wshDDSYg1LYpcAUeQIV+9c4+ZcOe7Ex7p3INomeN4=; b=qBZzt1bNiOewZC2hyxNWkW6j+uSfWmxJZFNAPWI5xh8/3XGMBX+YlHsaz6lFzp6xAR UTxP4D1+X7d8X9Drp+ydoZlj1lkr/yVj7sSHtmKHY8COjuwn20YEwwQrTAnWBH3iw/WK mkLMgrbli156x7p+409aBo1ZqyyK8bFYsmu1h3/tb/R2DcSydan4ICRBn4rgu8pvWwR5 fJ8pJkQwJmGbeJZHmTvGqTjQ+9eaDzcyidZSaq04gy3QZxwIpnLwkUhZ/mC2THDnlaYm 7pJpcSeWIoA7/vBpQVgELc7qXzWc5llFur6NZsT1bSwLfzggjI2jZLy2tMPAFFoqOcEg 2KUg== X-Gm-Message-State: AOAM531rYUz6Vlgr4qAduHl5o2OspRqa/9MqNaUU28emNaF5jWbpwImc m5HXBgPlc49lop08P/JwbLY= X-Google-Smtp-Source: ABdhPJwBOPLslwkb0ySS95Ox36T31XmpkjOr+NNmYZvlMknV5I1h3TMHPpse4NorHh5CiHRvsZ19Vg== X-Received: by 2002:a17:90a:8c91:: with SMTP id b17mr7641252pjo.74.1595989700830; Tue, 28 Jul 2020 19:28:20 -0700 (PDT) Received: from sol (106-69-185-93.dyn.iinet.net.au. [106.69.185.93]) by smtp.gmail.com with ESMTPSA id v11sm364987pgs.22.2020.07.28.19.28.16 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 28 Jul 2020 19:28:19 -0700 (PDT) Date: Wed, 29 Jul 2020 10:28:14 +0800 From: Kent Gibson To: Andy Shevchenko Cc: Linux Kernel Mailing List , "open list:GPIO SUBSYSTEM" , Bartosz Golaszewski , Linus Walleij Subject: Re: [PATCH v2 05/18] gpiolib: cdev: support GPIO_GET_LINE_IOCTL and GPIOLINE_GET_VALUES_IOCTL Message-ID: <20200729022814.GA1750878@sol> References: <20200725041955.9985-1-warthog618@gmail.com> <20200725041955.9985-6-warthog618@gmail.com> <20200726011244.GA6587@sol> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20200726011244.GA6587@sol> Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Sun, Jul 26, 2020 at 09:12:44AM +0800, Kent Gibson wrote: > On Sat, Jul 25, 2020 at 11:51:54PM +0300, Andy Shevchenko wrote: > > On Sat, Jul 25, 2020 at 7:24 AM Kent Gibson wrote: > > > [ snip ] > > > + test_bit(line_idx, (unsigned long *)lc->attrs[i].mask)) > > > > This casting is not good. What about BE 32-bit architecture? > > > > I agree the casting is hideous, but I thought the outcome was correct > as it is manipulating addresses, not data. > You think the address of a 64-bit differs based on endian?? > Happy to change it - but not sure what to. > You are right - using bitops on u64 is problematic for BE-32 - the 32-bit words will be swapped if userspace treats the flags as the u64 it is defined as. I'll rework that for v3. Cheers, Kent.